100644 blob 8bd6648ed130ac9ece0f89cd9a8fbbfd2608427a	a
100644 blob 8bd6648ed130ac9ece0f89cd9a8fbbfd2608427a	b
040000 tree aaa44111ab9ec12e5ccc8eb26a6f1e2c8733c55e	dir_a
040000 tree 2b16780317c104cb7adb8d0528c550bc4c4948b9	dir_b